A flat-six engine, often referred to as a horizontally opposed-six, has three cylinders on each side of the central crankshaft, making it a six-cylinder piston engine. The Porsche 911 sports vehicle, which has employed flat-six engines constantly since 1963, is the most renowned application of these engines.
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Flat-six Porsche engine
The Porsche flat-six engine series is a line of mechanically comparable flat-sixboxer engines that have been produced by Porsche since 1963 for almost 60 years without interruption. The flat-fourboxer utilized in the first Volkswagen Beetle has been evolved into the current engine.
The 911 model, Porsche’s flagship rear-engined sports car that has only employed flat-six engines since 1963, is most frequently associated with the flat-six engine. Up until 1999, when Porsche began using water-cooled engines, the engines were air-cooled.
Porsche unveiled the third iteration of the 997 GT3 RS in April 2011 with a larger 4.0-liter engine that produces 500 PS (368 kW; 493 hp). With their 911 (997) GT3 RS 4.0, which debuted in 2011, they debuted the naturally aspirated 4.0-liter flat-six engine, the largest engine available in a street-legal 911. The engine itself makes use of an RSR crankshaft with larger stroke specifications (from 76.4 mm to 80.4 mm). A power-to-weight ratio of 365 horsepower per ton was achieved thanks to this modification, which increased the output to 500 PS (368 kW; 493 hp) at 8,250 rpm and 460 Nm (339 lbft) of torque at 5,750 rpm. There were just 600 automobiles made. The engine’s 493 horsepower (368 kW) and 123.25 horsepower (92 kW) per liter output make it one of the most potent six-cylinder naturally aspirated engines in a production vehicle.
The 1970–1972 Porsche 914/6 (mid-engine), the 1986–1993 Porsche 959 (rear-engine), and the 1996–2021 Porsche Boxster/Cayman are further Porsche models powered by flat–six engines (mid-engine).
The custom of the flat engine
The 911’s silhouette and flat engine are frequently the first images that come to mind when someone thinks about Porsche. Every Porsche enthusiast holds these engines in the highest regard. But what makes this specific internal combustion engine design principle so unique?
Fans of this engine type have a soft spot in their hearts for air-cooled flat engines. But feelings only provide a partial picture. The flat engine has a number of intriguing qualities that give it the advantage from a design standpoint in addition to roaring its way into the hearts of many. Its beginnings can be traced back 122 years to Carl Benz’s invention of the flat engine in 1896. Because its two cylinders operated counter to one another, he termed it the contra engine. The original boxer engine was designed to have a displacement of more than 1.7 liters and produce 5 horsepower. The essential design guideline is that the cylinders should be positioned on either side of the crankshaft, level and slightly offset from one another.
The VW Beetle is the ancestor of the flat engines used in Porsche vehicles. Ferry Porsche placed its 26 kW (35 hp), 1.1-liter, four-cylinder engine in his 356-001. Up until the 911 Type 993, all ensuing engines were air-cooled. Without using a turbocharger, the 3.8-liter air-cooled flat engine in the top-of-the-line 911 Carrera RS produced 221 kW (300 horsepower). Performance was increased by two turbochargers to 331 kW. (450 hp).
The New Flat-6 Engine from Porsche May Be Used in Other Models
Porsche recently unveiled the GT4 version of the 718 Cayman and the Spyder version of the 718 Boxster, two high-performance variations of already-available vehicles in its lineup. A brand-new flat-6 engine that was created for them powers both.
Even yet, it might not have been exclusively for them. Porsche recently revealed that it had more ambitious aspirations for this new unit than simply using it to support two specialized goods. The 6-cylinder engine is anticipated to spread to further models across the company’s line of products.
According to Andreas Preuninger, head of Porsche’s GT division, the new 4.0 engine in question bears almost little resemblance to the 3.0L 6-cylinder engine that drives the 911. The CEO revealed to the Car & Throttle website that his team created a number of pieces for the new engine, including cylinder heads, pistons, housing, crankshaft, and crankshaft. Because the 911S engine cannot fit in the 718, the firm took this pricey action. A 4 cylinder turbo engine was also decided to be untrustworthy in the eyes of many potential customers.
We support normally aspirated engines, particularly for vehicles that fit that description—puristic vehicles. To be really honest with you, we might also use this engine in the future on other models.
The CEO did neither confirm or deny that the new engine would be installed in the 911.
Porsche has omitted from this discussion the fact that the 4-cylinder engine available in the latest Cayman and Boxster has not gotten positive reviews from all consumers. For instance, the 718 has had a difficult time in sales so far in 2019; Porsche has sold 30% fewer of the model in both the United States and Canada. The fact that the new 6-cylinder engine complies with European emissions and noise norms is great news for Porsche. Even more justification for it to eventually appear in regular 718 cars.
How the outstanding air-cooled flat-six engine from Porsche survived for three decades
In the past fifty years, automobile aficionados have called 911 more than a million times—not for help in an emergency, but rather to obtain the vehicle that best captures Porsche’s spirit. The rear-mounted six-cylinder engine, which is the 911’s heart and soul, is cooled by fins and a fan. The crankshaft of this engine is in the center, and three cylinders are arranged flat on each side. The 911 engine offers dazzling performance and a vibrant personality, far exceeding what you might anticipate from a configuration that is descended from the VW Beetle. Since 1965, parishioners have been drawn to the Porsche religion by this alluring combination.
The turning point came in 1963 at the Frankfurt Motor Show, when Porsche unveiled the 901, the replacement for its four-cylinder 356 sports vehicle. Peugeot, on the other hand, took issue with the moniker since it claimed ownership of all three-digit model designations with a zero in the center. Before the 911 was sold to European customers in 1964 and to Americans the following year, the 901 was renamed. Nothing prevented Porsche from maintaining the 901 code for internal usage, thus the flat-six engine used in the 911 was given that name.
What’s the difference, re: H6 and F6
Yes, the “H” engine has more than one crankshaft, but I don’t believe the “H” engine is related to “horizontal” engines in any way. The engines in Porsche cars are often referred to as “horizontally opposed” engines because they have three pistons on each side of a central crankshaft that are positioned in opposition to one another in a horizontal plane. Although these are flat fours, air-cooled Subaru and Volkswagen motors are also horizontally opposed. BMW produces a horizontally aligned, four-cylinder motorcycle engine, but because all the pistons are on one side, it is not “horizontally opposed.” They are also well known for their horizontally opposed, air-cooled twin motorcycle engine.
Porsche 2.7L DOHC DI H-6 won.
Porsche deserves praise for producing a little, naturally aspirated engine with such strong feelings and sounds. Every sports car manufacturer needs to have an engine like this to succeed as CAFE rules rise in the United States. It is efficient yet terrifyingly entertaining.
It may be argued, at the risk of upsetting readers, that creating top-notch automobiles shouldn’t be all that challenging since it all comes down to one fundamental idea: increasing power while minimizing weight.
Of course, every carmaker talks about inventive uses for cutting-edge materials and inventive ways to occasionally save a few pounds.
However, if your line of work involves German sports automobiles, the leash tends to be longer, the costs will be higher, and the opportunity to produce truly exceptional results is multiplied as product designers work to update a particular model.
The brand-new Porsche Cayman and its convertible platform companion, the Boxster, experienced exactly that.
On paper, the 2.7L horizontally opposed 6-cyl. base engine in these automobiles produces 275 horsepower and a measly 213 lb.-ft. (289 Nm) of torque, which is extremely low by today’s standards.
But fasten this jetpack behind the two seats, turn the key, and it’s clear why Porsche’s new 2.7L flat-6 engine has earned its fourth Ward’s 10 Best Engines honor.
The argument about conserving weight while boosting power becomes glaringly obvious when you shift the 2,888-lb (1,310-kg) coupe into gear, give the engine a chance to work a bit more of its audible magic, and go for a brief trip around the twisties.
However, it is not necessary because the 2.7L and the Cayman’s chassis are excellent companions that are so much more than the sum of their parts. Porsche is happy to supply extra power for clients who want to pony up for a larger engine or possibly one that is turbocharged.
The mid-mounted 2.7L H-6 in the Cayman/Boxster produced 245 horsepower and 201 lb.-ft. (272 Nm) of torque at the last competition, which took place in 2008. In a sea of high-output 6-cyl. engines, it was passed over, and for a split second, it appeared as though Porsche had lost its edge.
However, the brand-new water-cooled 2.7L engine is better all around thanks to stop/start, direct injection, VarioCam Plus variable valve timing and lift on the intake cam, an alternator that sends more energy to the battery during braking and coasting, and a PDK dual-clutch transmission that enables more coasting, allowing the engine to use as little fuel as necessary to remain at idle under certain driving conditions.
Combining these technologies with aggressive weight reduction, the Cayman with a 6-speed manual transmission obtains an EPA rating of 20/30 mpg (11.7-7.8 L/100 km), which is almost comparable to the 2.5L 4-cyl. standard engine in the Chevrolet Impala while weighing much more.
The Cayman would have been in the running even without our decision to raise the price cap from $55,000 to $60,000. Its basic price with the 2.7L is just over $52,000.
Porsche deserves praise for producing a little, naturally aspirated boxer with such strong feelings and sounds. This is the kind of effective yet terrifyingly entertaining engine that every sports car manufacturer needs to succeed as CAFE rules rise in the United States.
Porsche uses flat-6 engines for what reason?
The air-cooled flat engine is the best option for sports cars since it is flat, lightweight, and allows for exceptionally low designs because the cylinders are lying flat. Because of the lowered center of gravity, it is possible to drive in a sportier, more dynamic manner throughout the entire driving maneuver. Because the flat engine’s weight sits on the drive axle when mounted at the back, as it is in Porsche cars, traction is enhanced. Drivers of Beetle and Porsche concurred that a car with a rear-mounted engine was by far the greatest option for winter driving conditions prior to the advent of all-wheel drive automobiles. The contrary is also true: A rear-mounted engine’s weight enables more braking force to be applied to the rear wheels during braking.
The flat engine, especially the six-cylinder version, is exceptionally smooth to operate and has no free moments or forces. Because of the perfect balance of the crank mechanism, short-stroke sports engines may travel at high speeds without experiencing undue strain.
The Porsche six-cylinder flat engines’ tendency to use less fuel as engine power rises is one of their most distinguishing characteristics. The flat engine’s design idea is around a consistent lightweight build, a low center of gravity, exceptional revving prowess, and a high specific output due to favourable charge cycles. All 911 engines must be both sporty and practical for daily use.
In general, a flat engine requires more work to produce than an in-line engine since it requires more parts. Two banks of cylinders, a valve train, cooling, and/or injection are required for the flat engine. Because the individual cylinders of a flat engine are spaced far away from one another, they can benefit from a direct flow of cooling air, making this engine a particularly strong option for air cooling. The four-valve technique is principally responsible for the 911 flat engines being water-cooled since the 996 model series. To reduce fuel consumption and exhaust pollutants while also improving performance, four valves are necessary.
But only lovers of water-cooled flat engines will find this interesting. There isn’t a club by that name yet, but when these engines stop being the newest technology and enter the annals of history, there will undoubtedly be one.